Wheelbarrow extension



FIG. 1 is a side elevational view of a wheelbarrow extension showing our new design;

FIG. 2 is another side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a front view thereof.

The broken line showing in FIG. 1 is included for the purpose of illustrating environment and forms no part of the claimed design. 

The ornamental design for a wheelbarrow extension, as shown and described. 